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Diffstat (limited to 'console/bridge.go')
-rw-r--r-- | console/bridge.go | 317 |
1 files changed, 317 insertions, 0 deletions
diff --git a/console/bridge.go b/console/bridge.go new file mode 100644 index 000000000..b23e06837 --- /dev/null +++ b/console/bridge.go @@ -0,0 +1,317 @@ +// Copyright 2015 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>. + +package console + +import ( + "encoding/json" + "fmt" + "io" + "time" + + "github.com/ethereum/go-ethereum/logger" + "github.com/ethereum/go-ethereum/logger/glog" + "github.com/ethereum/go-ethereum/rpc" + "github.com/robertkrimen/otto" +) + +// bridge is a collection of JavaScript utility methods to bride the .js runtime +// environment and the Go RPC connection backing the remote method calls. +type bridge struct { + client rpc.Client // RPC client to execute Ethereum requests through + prompter UserPrompter // Input prompter to allow interactive user feedback + printer io.Writer // Output writer to serialize any display strings to +} + +// newBridge creates a new JavaScript wrapper around an RPC client. +func newBridge(client rpc.Client, prompter UserPrompter, printer io.Writer) *bridge { + return &bridge{ + client: client, + prompter: prompter, + printer: printer, + } +} + +// NewAccount is a wrapper around the personal.newAccount RPC method that uses a +// non-echoing password prompt to aquire the passphrase and executes the original +// RPC method (saved in jeth.newAccount) with it to actually execute the RPC call. +func (b *bridge) NewAccount(call otto.FunctionCall) (response otto.Value) { + var ( + password string + confirm string + err error + ) + switch { + // No password was specified, prompt the user for it + case len(call.ArgumentList) == 0: + if password, err = b.prompter.PromptPassword("Passphrase: "); err != nil { + throwJSException(err.Error()) + } + if confirm, err = b.prompter.PromptPassword("Repeat passphrase: "); err != nil { + throwJSException(err.Error()) + } + if password != confirm { + throwJSException("passphrases don't match!") + } + + // A single string password was specified, use that + case len(call.ArgumentList) == 1 && call.Argument(0).IsString(): + password, _ = call.Argument(0).ToString() + + // Otherwise fail with some error + default: + throwJSException("expected 0 or 1 string argument") + } + // Password aquired, execute the call and return + ret, err := call.Otto.Call("jeth.newAccount", nil, password) + if err != nil { + throwJSException(err.Error()) + } + return ret +} + +// UnlockAccount is a wrapper around the personal.unlockAccount RPC method that +// uses a non-echoing password prompt to aquire the passphrase and executes the +// original RPC method (saved in jeth.unlockAccount) with it to actually execute +// the RPC call. +func (b *bridge) UnlockAccount(call otto.FunctionCall) (response otto.Value) { + // Make sure we have an account specified to unlock + if !call.Argument(0).IsString() { + throwJSException("first argument must be the account to unlock") + } + account := call.Argument(0) + + // If password is not given or is the null value, prompt the user for it + var passwd otto.Value + + if call.Argument(1).IsUndefined() || call.Argument(1).IsNull() { + fmt.Fprintf(b.printer, "Unlock account %s\n", account) + if input, err := b.prompter.PromptPassword("Passphrase: "); err != nil { + throwJSException(err.Error()) + } else { + passwd, _ = otto.ToValue(input) + } + } else { + if !call.Argument(1).IsString() { + throwJSException("password must be a string") + } + passwd = call.Argument(1) + } + // Third argument is the duration how long the account must be unlocked. + duration := otto.NullValue() + if call.Argument(2).IsDefined() && !call.Argument(2).IsNull() { + if !call.Argument(2).IsNumber() { + throwJSException("unlock duration must be a number") + } + duration = call.Argument(2) + } + // Send the request to the backend and return + val, err := call.Otto.Call("jeth.unlockAccount", nil, account, passwd, duration) + if err != nil { + throwJSException(err.Error()) + } + return val +} + +// Sleep will block the console for the specified number of seconds. +func (b *bridge) Sleep(call otto.FunctionCall) (response otto.Value) { + if call.Argument(0).IsNumber() { + sleep, _ := call.Argument(0).ToInteger() + time.Sleep(time.Duration(sleep) * time.Second) + return otto.TrueValue() + } + return throwJSException("usage: sleep(<number of seconds>)") +} + +// SleepBlocks will block the console for a specified number of new blocks optionally +// until the given timeout is reached. +func (b *bridge) SleepBlocks(call otto.FunctionCall) (response otto.Value) { + var ( + blocks = int64(0) + sleep = int64(9999999999999999) // indefinitely + ) + // Parse the input parameters for the sleep + nArgs := len(call.ArgumentList) + if nArgs == 0 { + throwJSException("usage: sleepBlocks(<n blocks>[, max sleep in seconds])") + } + if nArgs >= 1 { + if call.Argument(0).IsNumber() { + blocks, _ = call.Argument(0).ToInteger() + } else { + throwJSException("expected number as first argument") + } + } + if nArgs >= 2 { + if call.Argument(1).IsNumber() { + sleep, _ = call.Argument(1).ToInteger() + } else { + throwJSException("expected number as second argument") + } + } + // go through the console, this will allow web3 to call the appropriate + // callbacks if a delayed response or notification is received. + blockNumber := func() int64 { + result, err := call.Otto.Run("eth.blockNumber") + if err != nil { + throwJSException(err.Error()) + } + block, err := result.ToInteger() + if err != nil { + throwJSException(err.Error()) + } + return block + } + // Poll the current block number until either it ot a timeout is reached + targetBlockNr := blockNumber() + blocks + deadline := time.Now().Add(time.Duration(sleep) * time.Second) + + for time.Now().Before(deadline) { + if blockNumber() >= targetBlockNr { + return otto.TrueValue() + } + time.Sleep(time.Second) + } + return otto.FalseValue() +} + +// Send will serialize the first argument, send it to the node and returns the response. +func (b *bridge) Send(call otto.FunctionCall) (response otto.Value) { + // Ensure that we've got a batch request (array) or a single request (object) + arg := call.Argument(0).Object() + if arg == nil || (arg.Class() != "Array" && arg.Class() != "Object") { + throwJSException("request must be an object or array") + } + // Convert the otto VM arguments to Go values + data, err := call.Otto.Call("JSON.stringify", nil, arg) + if err != nil { + throwJSException(err.Error()) + } + reqjson, err := data.ToString() + if err != nil { + throwJSException(err.Error()) + } + + var ( + reqs []rpc.JSONRequest + batch = true + ) + if err = json.Unmarshal([]byte(reqjson), &reqs); err != nil { + // single request? + reqs = make([]rpc.JSONRequest, 1) + if err = json.Unmarshal([]byte(reqjson), &reqs[0]); err != nil { + throwJSException("invalid request") + } + batch = false + } + // Iteratively execute the requests + call.Otto.Set("response_len", len(reqs)) + call.Otto.Run("var ret_response = new Array(response_len);") + + for i, req := range reqs { + // Execute the RPC request and parse the reply + if err = b.client.Send(&req); err != nil { + return newErrorResponse(call, -32603, err.Error(), req.Id) + } + result := make(map[string]interface{}) + if err = b.client.Recv(&result); err != nil { + return newErrorResponse(call, -32603, err.Error(), req.Id) + } + // Feed the reply back into the JavaScript runtime environment + id, _ := result["id"] + jsonver, _ := result["jsonrpc"] + + call.Otto.Set("ret_id", id) + call.Otto.Set("ret_jsonrpc", jsonver) + call.Otto.Set("response_idx", i) + + if res, ok := result["result"]; ok { + payload, _ := json.Marshal(res) + call.Otto.Set("ret_result", string(payload)) + response, err = call.Otto.Run(` + ret_response[response_idx] = { jsonrpc: ret_jsonrpc, id: ret_id, result: JSON.parse(ret_result) }; + `) + continue + } + if res, ok := result["error"]; ok { + payload, _ := json.Marshal(res) + call.Otto.Set("ret_result", string(payload)) + response, err = call.Otto.Run(` + ret_response[response_idx] = { jsonrpc: ret_jsonrpc, id: ret_id, error: JSON.parse(ret_result) }; + `) + continue + } + return newErrorResponse(call, -32603, fmt.Sprintf("Invalid response"), new(int64)) + } + // Convert single requests back from batch ones + if !batch { + call.Otto.Run("ret_response = ret_response[0];") + } + // Execute any registered callbacks + if call.Argument(1).IsObject() { + call.Otto.Set("callback", call.Argument(1)) + call.Otto.Run(` + if (Object.prototype.toString.call(callback) == '[object Function]') { + callback(null, ret_response); + } + `) + } + return +} + +// throwJSException panics on an otto.Value. The Otto VM will recover from the +// Go panic and throw msg as a JavaScript error. +func throwJSException(msg interface{}) otto.Value { + val, err := otto.ToValue(msg) + if err != nil { + glog.V(logger.Error).Infof("Failed to serialize JavaScript exception %v: %v", msg, err) + } + panic(val) +} + +// newErrorResponse creates a JSON RPC error response for a specific request id, +// containing the specified error code and error message. Beside returning the +// error to the caller, it also sets the ret_error and ret_response JavaScript +// variables. +func newErrorResponse(call otto.FunctionCall, code int, msg string, id interface{}) (response otto.Value) { + // Bundle the error into a JSON RPC call response + res := rpc.JSONErrResponse{ + Version: rpc.JSONRPCVersion, + Id: id, + Error: rpc.JSONError{ + Code: code, + Message: msg, + }, + } + // Serialize the error response into JavaScript variables + errObj, err := json.Marshal(res.Error) + if err != nil { + glog.V(logger.Error).Infof("Failed to serialize JSON RPC error: %v", err) + } + resObj, err := json.Marshal(res) + if err != nil { + glog.V(logger.Error).Infof("Failed to serialize JSON RPC error response: %v", err) + } + + if _, err = call.Otto.Run("ret_error = " + string(errObj)); err != nil { + glog.V(logger.Error).Infof("Failed to set `ret_error` to the occurred error: %v", err) + } + resVal, err := call.Otto.Run("ret_response = " + string(resObj)) + if err != nil { + glog.V(logger.Error).Infof("Failed to set `ret_response` to the JSON RPC response: %v", err) + } + return resVal +} |